var platform="";
if (navigator.appVersion.indexOf("Mac")!=-1) platform = "mac";

if (platform == "mac") {
<!-- vars offset left (no. of entries equals number of dropdown menus i.e. 3 menus equals 3 values here//--> 
var menu_OffSet = [83,165,291,610];
}

else if (platform != "mac") { 
var menu_OffSet = [83,165,291,610];
} 

var menus = [
<!-- vars offset down and depth of menu -  ??, height from top, width, depth//--> 
new ypSlideOutMenu("menu1", "down", 98, 133, 115, 330),
new ypSlideOutMenu("menu2", "down", 98, 133, 115, 330),
new ypSlideOutMenu("menu3", "down", 98, 133, 180, 500),
new ypSlideOutMenu("menu4", "down", 98, 133, 90, 330)
]
for (var i = 0; i < menus.length; i++) {

menus[i].onactivate = new Function("var newLeft = menu_OffSet[" + i + "]; menus[" + i + "].container.style ? menus[" + i + "].container.style.left = newLeft : menus[" + i + "].container.left = newLeft;")

}
function getWindowWidth()

{

return window.innerWidth ? window.innerWIDTH: document.body.offsetWidth;

}